Web drying method and device



Dec. 29, 1942. H I "2,306,607

I WEB DRYING METHOD- AND DEVI/CBS Filed Dec. 30-, 19:51 4 2 Sheets-Sheet1 fi t 4 INVE2NTOR. L A L \JZLb enZLI HOr EO f i I a Dec. 29, 1942. A.J. HORTON 2,306,607

WEB DRYING'METHODY AND DEVICES Filed Dec. 50, 1937 2 smug-sheet 2m'v'zu'roa.

Patented Dec. 29, 1942 UNITED STATES lA'lENT 'oFF'iicE 2,306,607 wasname Ms'rnon AND DEVICE Albert J. nei-ien, White Plains, N. in, minor toR. Hoe & 00., Inc., New York, N. Y., a corpora tion of New YorkApplication December 30, 1937, Serial No. 182,594

3 Claims. (01. 34-23) ders and led over aheated drum or subjected to thedrying action of .preferably heated air.

When the web is thus heated, its moisture content is greatly reducedthereby resulting in variation in length of the web with the. consequentdifiiculty in effecting accurate register during the printingoperationsg Furthermore, the lack of requisite moisture in the papercauses it to become roughened and its strength weakened.

Attempts have been made to moisten the web during the drying operationby passing the freshly printed'web through an'enclosure or housing intowhich aqueous vapor is fed in the form of 2 including an enclosure orduct communicating.

steam jets which impinge heated air circulated in the enclosure orhousing about the web. With such method, however, it is difllcult toaccurately control the moisture content of the drying air, because anexcess quantity of steam raises the percentage of humidity in the dryingair to a degree that interferes with the proper drying of the web.

An object, therefore, of this invention is to provide a method of andmechanism for drying a freshly printed web or sheet by subjecting thefreshly printed web or sheet to the drying action of heated air to whichaqueous vapor is added in accurately controlled quantities to therebymaintain the moisture content of the web substantial- -ly constantthroughout the entire web drying operation. 7

Another object of this invention is to providemeans for drying a freshlyprinted web by passing the web through an enclosure or housing to 40which heated air. is supplied, and passing the heated air over areceptacle containing water so that the air is thus properly humidifiedbefore impinging the web.

A further object of this invention is to provide heated air in passingthrough the enclosure or duct on its way to the web housing passing overa receptacle-containing water or other suitable liquid in accuratelycontrolled quantity, so that the heated air picks up the requisitequantity of of moisture content in the web-drying air durin the entireweb drying operation. 1 I

A specific object of this invention is to provide a web drying device inwhich a freshly printed web is led through a housing and heated airdirected through an enclosure or duct into the housing and circulatedtherein against the web,

7 the heated air in passing through the duct on its way to the webhousing passing over a receptacle or receptacles containing water orother suitable liquid in predetermined quantity, and

the area of water surface exposed to the passing heated air beingcontrollable so that the heated air'picks up the requisite quantity ofmoisture to maintain a predetermined percentage f moist'ure content inthe web-drying air during the drying operation.

A more specific object of this invention is to provide a web dryingdevice in which a freshly printed web is led through a housing, the'device with the housing, a liquid-containing recept cle located withinthe duct and communicating ith a source of liquid supply, heating meansloc ted in the duct in advance of the liquid container to thereby heatair passing through the duct on its ,way to the web housing before thisair passes the quantity of liquid supplied to the container, the

container being arranged to expose the liquid to the passing heated airthroughout a surface area which isdetermined by the quantity of liquidin the container, so that the heated air in passing the exposed surfaceof the liquid picks up the requisite quantity of moisture to maintain adetermin'ed percentage of moisture content in the durable andinexpensive in construction, as well as convenient, practical andserviceable in. its

use. v p

With the foregoing and other objects in view, which will appear as thedescription proceeds.

theihvention resides in the combination and arrangement of parts, and inthe details of construction hereinafter described and claimed, it beingunderstood that various changes'in form, proportion, and minor detailsof construction may be made within the scope of the claims withoutdeparting, from the spirit or sacrificing any advantages of theinvention.

For a complete disclosure of the invention, a moisture to maintain adeterminedpercentage detailed description of it will now be given inwith an exhaust Figure 4 is a detail elevation looking in the directionof the arrow 4 in Figure 3 and depicting the adjusting mechanism for theliquid level con-.

trol float, and

Figure 5 is a vertical longitudinal sectional view taken through amodified air conveying and humidifying duct.

Referring to the drawings in which similar reference charactersdesignate corresponding parts, there is depicted a machine frame l0arranged to support a plurality of printing units H, but, in-

asmuch as these units are similarly constructed,

only one unit is shown in the drawings of this application. Eachprinting unit includes an intaglio form cylinder l2 and a cooperatingimpression cylinder l3. The impression cylinder I3 is engaged by spacedrollers M which reinforce it against movement away from the formcylinder l2 during the printing operation. This printing unit is ofconventional construction well known to and understood by those skilledin the art, therefore, it is thought that no further disclosure thereofneed be made in this application.- I

- A plurality of web guide rollers |5 are provided to guide a web W tothe printing unit from another unit or from a suitable web supply, notshown. The web'W is guided from the printing unit H by a plurality ofrollers l6 operably supported in a fan casing 34, that, in turn,communicates with an exhaust pipe which may lead to. any preferreddestination. Suitably constructed blower type centrifugal fans 36 and 31are operably disposed in the casings 26 and 34,

respectively, and these fans are rotated by an electric motor- 38 ofconventional construction mounted upon a component of the machine frameI0.

'A housing 4| extends downwardly" from the drum and is provided with afront wall 42 and a rear wall 43, the housing being best shown inFigure 1. Between the front and rear walls 42 and 43 spaced partitions44 and 45 are provided, which, together with the walls 42 and 43 formseparate ducts 48, 41 and 48. The duct 46, formed by the front wall 42and the partition 44, is in communication with a chamber 49 formedwithin the drum 20 at the exhaust side of the partition 2| through anelongated opening 5| formed in the wall of the drum at the side of thepartition 2| which is disposed towards the exhaust conduit 33. The

duct 48 formed by the rear wall 43 and the p'arti 3 disposed towards theintake conduit 25. A wall web drying device H of known constructionwhich is hereinafter described and which is also disclosed in UnitedStates Patent No. 2,126,778, granted to Albert J. Horton on August 16,1938. After the web leaves the web drying device I1, it is guided byrollers I8 to the next printing unit or to the delivery mechanism of theprinting machine, but,

inasmuch as such delivery mechanism forms no part .of this invention ithas not been depicted in I the drawings of this application.

An improved web drying device is provided which includes a hollowcylindrical drum 28 having a transverse partition 2| therein, asindicated in Figure 2, for a purpose to be hereinafter dis is spacedfrom and parallels a portion of the wall 42, and this wall and itsmarginal flanges provide a receptacle. which'houses the web guiderollers l6. ported by a bracket or a component of the machine frame sothat the air supply or directing device may be swung on its supportingrollers 22 away from the wall 55 to permit access to the web guideroller l8. Theair receptacle 56 is in communication with the duct 46through an elongated pas sage 51 which extends substantially across theentire width of the front wall 42 of the housing 4|. The air receptacle58 is in communication with the I ducts 41 and through similarly formedelonclosed. The opposed terminals of the drum 28 are preferablyrotatably supported'uponantifriction rollers22 mounted on brackets 23forming componentsof the machine frame ID. A stationary intake conduit25 is connected to one end of the drum 20 and communicates with a fancasing 28 which is, in turn, communicated with an air intake conduit 21.A heating unit is provided and includes a plurality of parallel pipesections 28 having their adjacent terminals interconnected by U-shapedpipe sections 38, and one terminal pipe 28 of the heating unit isconnected with an intake pipe 3|, and the opposed terminal pipe 28 isconnected with an outlet pipe 32. The pipe 3| communicates with anysuitable source of heated fluid supply, preferably steam, to therebycause the heating-unit to heat air passing through the conduit 21, aswill be hereinafter explained. The pipe 32 may lead back to the sourceof steam supply or to any suitable exhaust terminal not shown. The otherterminal of the drum 28 is connected with an exhaust conduit 33 whichcommunicates gated passages 88 and 58 respectively. This arrangement forsupplying air currents to the running web is disclosed in thehereinbefore cited Horton Patent No. 2,126,778.

When it is desired to subject the running web W to the drying" influenceof air currents, the fans 38 and 31 are rotated to cause a flow of airfrom the conduit 21, through the casing 26 and intake conduit 25, intothe chamber 53 formed" in the intake end of the-drum 20, and from thischamber 53 through the opening 54, duct 41 and passage 58 to the web W.-The air upon impinging the web spreads and flows in opposed directionover the printed surface of the web' thereby drying the ink byevaporation of the ink solvents. This air is then exhausted from the Ireceptacle 58 through the passages 51 and 59 into the ducts 48 and 48respectively, from which it flows through openings 5| and 52 into thechamber 48 formed in the exhaust end of the drum 28, and from therethrough the conduit 33 and the fan casing 34 into the exhaust pipe 35through which it is directed to any preferred destination.

The incoming air in passing through the conduit 21 is heated by the coilor pipes 28 and then conveyed, as hereinbefore disclosed, to the runningweb. It has been found that while heated This wall may be independentlysuppan or receptacle 8|.

air rapidly dries the web by evaporating the ink solvents, it has F'alsobeen observed that the resultant lowered relative humidity of the webdrying air aflects the'length of the web, reduces its strength androughens its surface. In 'order to increase the moisture content of theweb drying air to the requisite degree, the conduit 21 is enlarged, asindicated at 88, for the reception of superposed pans or receptaclesv81. While two pans 6| have been'depicted as disposed in superposedrelation, it is of course to beunderstood An inlet port 68 is provided"for each pan or receptacle 8i, and this port terminates in afrusto-conical valve seat 81 positioned within the A pipe nipple orsection 88 is threaded into the. outer terminal of each inlet port 86,and the pipe nipples 68 communicate with a supply pipe 18 throughinterposedbranch pipes 1l,.the supply pipe 18 leading to any source ofliquid supply, preferably water, which supplies the moistening liquidfor the pans or receptacles 6|, as will be hereinafter more fullydisclosed. A conical valve 121s arranged to operably engage each valveseat 81, and each valve 12 is supported by a valve, stem 18 slidablymounted in-a bearing 1| formed in a bracket 15 having a downwardlyextending marginal flange or apron 18 which serves as a-baiiie to directthe water supplied through the inlet port "towards the bottom of the panor receptacle 8!, as will be more fully explained hereinafter. The upperor outer terminal of each valve stem 18 is operably connected to thebifurcated head 11 of an arm 18 by a pin 88 which extends through thehead minal of the sleeve 85 by a screw 88, or other suitable securingdevice, and the outer terminal of the arm 88 has an adjusting screw 81threaded therethrough, as best shown in Figures 3 and 4,

which screwis preferably provided with a knurled manipulating head .82.The outer terminal of the shaft 82 has an arm 88 rigidly securedthereturn, heated by steam or other suitable heating fluid therebyraising the temperature of this air. As the heated air passes from thecoil or pipes 28 through the conduit 21, it passes over the surfaces ofthe water or fluid contained in the receptacles 8|, thereby picking upmoisture from the exposed water or liquid, and this moisture is thenconveyed through the-web housing to the web to sufficiently humidify theweb-engaging air to, prevent the heated air from changing the length ofthe web or to weaken .it or to roughen its surface. The quantity ofmoisture picked up from the pans or receptacles 8| is determined by thehygrometric state of the heated air, andgthe area of .water surfacesexposed, but, principally by the area of water surface exposed to thepassing air.

Inasmuch as each panor recept'acleiil is provided with an inclinedbottom, it is manifest that the water height or level within each pandetermines the area of water surface exposed to the passing air. Whenthe water level is low, as indicated in the upper pan in Figure 2, arelatively small water surface area is exposed to the air, but, when thewater level is raised, as indicated in the lower. pan in Figure 2, arelatively great surface area is exposed to the passing air.

The height of the water level in each pan can be readily adjusted bymanipulating the adjusting screw 81' to vary the angular relationbetween the arms- 88 and 88, which, through the interposed shaft 82 andsleeve 85, control the angular disposition of the float arm 81 relativeto the valve arm 18. By adjusting the angular relation between the floatarm 81 and the valve arm 18. the valve 12 may be regulated to engage itsseat 81 when the fluid head or level has reached a predetermined height.When the valve is opened, as indicated in the upper receptacle in Figure2, the incoming water impinges the baille "which directs the watertowards the bottom of the receptacle to prevent it splashing or flowingfrom the pan or receptacle GI, and, as-the fluid level reaches apredetermined height the valve 12 is closed, thus shutting of!additional supply of liquid. Thus itisseen that by manipulating theMadiusting screw 82, which is positioned exteriorly in Figure 5, anair-conveying conduit 21 is diato by a key 85, or other suitablesecuring device,

and the outer or free terminal of the arm 83 is positioned adjacent aterminal of the adjusting with the sleeve 85 through an interposed arm81, so that up and down movement of the float of the conduit 21, theoperator may conveniently control the area of fluid or water surfaceexposed to the air.

In the modified form of the invention disclosed closed, and the airpasses through this conduit on its way to the web housing, ashereinbefore disclosed. A water or fluid receptacle 8i is formed in. thebottom portion of the conduit 21', and suitable heating units or coils28' are preferably positioned in the receptacle 8| to thereby heat thewater or fluid within the receptacle. As the air passes from theatmosphere through the conduit 21', it picks up moisture from the heatedwater and conveys it to the web housing, as hereinbefore disclosed. Inorder to vary the amount of moisture picked vup by the air, a, leaf orbutterfly valve 88 is operably positioned within the conduit 21', and ithas one terminal pivotally secured at the intermediate portion of. theconduit, as indicated at 88. A manipulating handle [88 is 'swiveled orrotatably secured to the wall will oscillate the sleeve for a purpose tobe hereinafter disclosed.

In operation, the incoming air passes through the conduit 21, and theninto the web housing and engages the web as hereinbefore explained. Theincoming'air as it passes through the conduit 21 is heated by the coilor pipes 28, which are, in

of the conduit 21., and a threaded stem iill extends inwardly from themanipulating handle I88. and threadedly engages a nut'lllz carried bythe valve 88, so that rotation of the manipulating ,handle I88 will movethe valve upwardly and downwardly about its pivotal or fulcrum point 88,as shown in Figure 5 of the drawings.

When a relatively great quantity of moisture is to be conveyed throughth conduit 21' to the web housing, the handle IE0 is manipulated toelevate the free terminal I03 of the valve 98 to thus direct arelatively great quantity of air directly over the exposed surface ofthe body of water in the receptacle 6|. If, however, a lesser quantityof moisture is to be conveyed to the web'housing, the manipulatinghandle I00 is rotated so that the outer or free terminal.

f I03 of the butterfly valve 98 is moved downwardly, thus directing thedesired portion of ,the

air passing through the conduit 21 over the valve 98 and away from thefluid receptacle 6!. From the foregoing it is manifest that the an ularpositionof the valve 98 within the conduit 21' determines the quantityof air passing over or impinging the exposed surface of the water bodycontained in the receptacle 6|, thereby accurately controlling thequantity of aqueous vapor conveyed from the receptacle 6! throug theconduit H to the web housing.

Having thus' described my invention, what I to increase the moisturecontent of the heated,

air as it passes from the heating unit through the conduitto the webwithin the enclosure, means for communicating the water receptacle witha source of water supply, a float supported by the water within thereceptacle. a valve controlled by the float to control the said watercommunicating means, and means operably interposed between the float andvalve and adjustable from a point outside the conduit to control theheight of the water level in the water receptacle.

2. The method of. drying ink oh a freshlyprinted web in multi-stagecolor printing which consists through an enclosure located betweensuccessive printing cylinders, supplying air under pressure through aconfined path of travel to the enclosure, heating the-air in theconfined path of travel, increasing the moisture content of the heatedair in the said confined path by passing the air over and in contactwith the exposed surface of a body of water, passing the moistureladenair through the enclosure in contact with the freshly-printed web, andvarying the moisture content of the heated air by varying the area ofthe exposed surface of the body of water.

3. The method of drying ink on a freshlyprinted web in multi-stage colorprinting which consists in passing the freshly-printed web through anenclosure located between successive printing cylinders, supplying airunder pressure through a confined path of travel to the enclosure,increasing the moisture content of the air in the confined path oftravel by passing the air over and in contact with the exposed surfaceofa heated body or water, passing the moistureladen air from thesaidconfined path through the enclosure in contact with the freshly-printedweb, and varying the moisture content of the air by varying the quantityof air passing immediately adjacent the exposed surface of the inpassing the. freshly-printed webv

